RestSharp AddJsonBody is Not Serializing Body Correctly

Question

I'm using RestSharp 106.11.7.

I'm trying to create a task on ADO. I'm using RestSharp as follows:

  var body = new AdoRequestBody
  {
    op = "add",
    path = "/fields/System.Title",
    from = null,
    value = "Sample task"
  };

  var request = new RestRequest("aStringPointingtoApi", Method.POST);
  request.AddJsonBody(body);

With this, the body is being serialized to:

  {
    "op": "add",
    "path": "/fields/System.Title",
    "from": null,
    "value": "Sample task"
  }

According to ADO API this is the correct body:

[
  {
    "op": "add",
    "path": "/fields/System.Title",
    "from": null,
    "value": "Sample task"
  }
]

I tried the body with array/list parenthesis in Postman and it's working. If I remove the array/list parenthesis it doesn't work.

This is the error message I get:

You must pass a valid patch document in the body of the request.

Someone here seems to have found a solution using Newtonsoft.Json.JsonConvert, which I don't want to use. https://github.com/restsharp/RestSharp/issues/1413#issuecomment-578302527

So, how do I get RestSharp to serialize my object inside an array parenthesis?

Answer 1

The API expects an array of AdoRequestBody objects and you are serializing a single object. As stated in comments, create an array with your single object, then serialize it for the request:

var body = 
  new AdoRequestBody[]
  { 
    new AdoRequestBody
    {
       op = "add",
       path = "/fields/System.Title",
       from = null,
       value = "Sample task"
    }
  };

 var request = 
  new RestRequest(
    "aStringPointingtoApi", 
     Method.POST);
 
 request.AddJsonBody(body);